The Twenty-sixth Amendment (Amendment XXVI) to the United States Constitution prohibits the states and the federal government from using age as a reason for denying the right to vote to citizens of the United States who are at least eighteen years old. The drive to lower the voting age from 21 to 18 grew across the country during the 1960s, driven in large part by the broader student activism movement protesting the Vietnam War. The impetus for drafting an amendment to lower the voting age arose following the Supreme Court's decision in Oregon v. Mitchell, 400 U.S. 112 (1970), which held that Congress may establish a voting age for federal elections, but not for state or local elections.

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